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Main engine cutoff! Eight and a half minutes of rocket-borne acceleration were suddenly over. The tremendous jolt of leaving the launch pad... the clang of empty booster rockets shearing away at Mach 3... the steady build of g-forces to a chest-squeezing three times the force of gravity. And now... silence. We were in orbit at Mach 25, hurtling around the planet at a speed of 8 km every second, and the engines were, at last, quiet. I unzipped a glove and let it slowly twirl in front of my helmet faceplate. We were in free fall.

Unstrapping from my downstairs seat, I grabbed a camera and floated awkwardly toward the flight deck to photograph our departing fuel tank. On the way, Endeavour's hatch window beckoned--the temptation to take a peek was too much for me. My reflection greeted me in the dark glass as I searched for my first glimpse of Earth from space. Peering through the looking glass, I wondered what I would see--after nearly/our years of training, and a lifetime of dreams, what would geography really look like?

No textbook could have prepared me for my personal discovery of the planet's face. A dark silhouette cut through the night sky, blotting out the stars. Its edge was rimmed with a delicate, robin's-egg blue, marking the literal end of the world and the beginning of my reeducation in geography. It would be a lesson I'd never forget.

I am an astronaut, a mission specialist aboard the space shuttle. To date I've had the privilege of flying on four missions, spending a total of about fifty-three days in space. Each mission--each field expedition--has required years of hard work and exacting preparation, culminating in a frenzy of activity in orbit to wring out the greatest amount of scientific return. But one cannot work in orbit without the exhilarating, ever-present view of our planet. The chance to study it, to learn it anew--not through a camera's lens or a satellite's digital sensors but through human eyes--is one I can't resist (Figure 1). Geography comes to life outside the orbiter's windows, and an astronaut can both confirm lifelong concepts about our planet and search for new patterns in Earth's complexity from this superb vantage point.

SEEING EARTH IN A NEW WAY

Scouting Earth from an orbital platform is both an unforgettable experience and a daunting task. The planet's beauty is overwhelming, and the view from a spacecraft can be enjoyed--even treasured--for the purely visual pleasure it brings. Yet making sense of the details during a ninety-minute sweep around the globe will challenge anyone's interpretive abilities and powers of observation. Getting the most out of an orbital field expedition requires a solid dose of preparation in geography and the earth sciences, mastery of an array of cockpit observation tools, and an ability to respond to those unexpected opportunities that are sure to make an appearance.

I have looked down at Earth for twenty-eight years, ever since I took up flying as an Air Force Academy cadet in Colorado. Six years as a military pilot trained me well as an observer. To that experience I added an understanding of what processes had shaped earth's surface through five years of graduate study in planetary science. But exploring Earth from a space shuttle would require some specialized education. My first mission assignment came in 1992, when I was teamed with Dr. Linda Godwin, the payload commander for the upcoming Space Radar Lab (SRL) mission (Jones 1995). Over the next two years Linda and I learned the fundamentals of space based remote sensing and helped develop the shuttle cockpit systems for our advanced imaging radar, built by the National Aeronautics and Space Administration (NASA) and the German and Italian space agencies (Evans, Plaut, and Stofan 1997; Evans and others 1999). Although Linda and I would have primary responsibility for radar operations onboard, the whole crew were, in effect, members of the science team "in the field," some 215 km above the planet's surface. …